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* Rosneft plans 500,000 bpd from four fields by 2019
* It once hoped for that volume from Vankor alone this year
* Vankor is crucial to supplying growing China market
By Katya Golubkova
MOSCOW, Oct 25 (Reuters) - Rosneft said on Fridayit was delaying peak production at a strategic oilfield inSiberia that will be pivotal to its ability to fulfil growingsales commitments to the Chinese market.
The Vankor field, originally planned to reach peak output of500,000 barrels per day this year, will now do so in 2019 - andonly with the help of three other fields acquired via thisyear's $55 billion takeover of TNK-BP.
Rosneft issued the new production guidance after Reutersreported exclusively this week that output at Vankor, thelargest field to enter production in Russia in 25 years, wouldfall short of earlier targets.
The state oil major plans to produce 25 million tonnes ofoil (500,000 bpd) by 2019 at the group including Vankor and thenew fields, Suzun, Tagul and Lodochnoye.
"Such a multifaceted approach ... will make it possible tosignificantly extend the production plateau, increase theeffectiveness of infrastructure use and significantly cutproject costs," it said.
Rosneft declined to comment on the production outlook atVankor alone.
Analysts are paying close attention to Rosneft's resourcebase, in particular to Vankor and Yuganskneftegas - thecompany's biggest producing asset at the moment - as as it plansto triple oil flows to China.
"Initially, Vankor alone had to pump 25 million tonnes byapproximately 2017. Now it seems that Vankor won't peak itselfat all while the peak will be reached thanks to Tagul, Suzun andLodochnoye," said analyst Andrey Polischuk at Raiffeisenbank.
Vankor, which has driven recent Russian output growth,pumped 435,000 bpd in September, official data shows. Russia isthe world's top oil producer with current output of 10.5 mln bpdbut its key producing region - West Siberia - is maturing.
"We cut our forecast for 2014-2016 to 465,000 bpd (atVankor) but with things looking like this it seems we will haveto cut further," Polischuk said.
FLOWS TO CHINA
Rosneft is increasing sales to China, with exports expectedto exceed 1 mln bpd in the coming years. It ships 300,000 bpdvia a spur of the Eastern Siberia-Pacific Ocean pipeline thatruns to China.
As Russia diverts more oil east to Asia through its pipelinenetwork, the main export blend it sells in Europe - Urals - isgaining on Brent, the North Sea benchmark grade, optimisingrevenues for the industry and the Russian state.
In comments to Reuters earlier this week, Rosneft said itdid not plan to cut supplies to the west to honour its Asiancommitments and said its production plans were on track to meetobligations.
"They are extending the life of projects to ensure stablevolumes for longer. It seems Rosneft decided that ... there isno point in hurrying - they are adjusting output toobligations," said Vitaly Kryukov, an analyst with IFD Kapitalbrokerage.
The latest contract with Sinopec to supply 200,000 bpd over10 years allows the Chinese firm to receive oil both from thewest and the east of Russia, meaning Rosneft could use swapoperations with other producers in East Siberia, such asSurgutneftegas.
